gdal_layers.cc

// GDAL_Test.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include <iostream>
#include "gdal/gdal_priv.h"
#include "gdal/ogrsf_frmts.h"

int main(int argc, char *argv[]) {
  GDALAllRegister();

  GDALDataset *poDS = static_cast<GDALDataset *>(GDALOpenEx(
    argv[1],
    GDAL_OF_VECTOR | GDAL_OF_VERBOSE_ERROR,
    NULL,
    NULL,
    NULL));

  if (poDS == NULL) {
    printf("Open failed: %s\n", CPLGetLastErrorMsg());
    exit(1);
  }
  printf("FileList\n");
  char **FileList = poDS->GetFileList();
  char *File = FileList[0];
  int i = 0;
  while (File != nullptr) {
    printf("File %d: %s\n", ++i, File);
    File = FileList[i];
  }

  printf("Driver Name: %s\n", poDS->GetDriverName());
  printf("Layer Count: %d\n", poDS->GetLayerCount());

  for (OGRLayer *Layer : poDS->GetLayers()) {

    Layer->ResetReading();
    printf("Layer Name: %s\n", Layer->GetName());
    printf("\tFeature Count: %lld\n", Layer->GetFeatureCount());

    for (const auto &Feature : Layer) {
      OGRGeometry *Geometry = Feature->GetGeometryRef();
      if (Geometry == nullptr) { continue; }

      OGRwkbGeometryType gt = Geometry->getGeometryType();

      switch (gt) {
        case wkbPoint: printf("w\tkbPoint\n"); break;
        case wkbPoint25D: printf("\twkbPoint25D\n"); break;
        case wkbLineString: printf("\twkbLineString\n"); break;
        case wkbPolygon: printf("\twkbPolygon\n"); break;
        default: printf("\tDefault\n"); break;
      }
    }
  }

  GDALClose(poDS);
}